For a gas circuit breaker for use in a high-voltage electric power system, a gas circuit breaker referred to as a puffer type is widely used. The puffer type gas circuit breaker uses an increase in an arc extinguishing gas pressure in the midway point of a contact opening operation, in which a compressed gas is blown to an arc produced between contacts for breaking an electric current.
In order to improve the breaking performance of the puffer type gas circuit breaker, a double motion system has been proposed in which a driven-side electrode, which is fixed in previously existing systems, is driven in the direction opposite to the driving direction of a driving-side electrode.
For example, PTL 1 proposes a system using a fork type lever. In PTL 1, a pin in association with the motion of driving-side components contacts the curved portion of a fork to rotate the fork type lever. The rotational motion is converted into reciprocating motion. in opening and closing directions. Thus, a driven-side arcing contact is driven in the direction opposite to the driving direction of a driving-side electrode. The position of the lever is maintained, with the pin being apart from the curved portion of the fork, and the driven-side arcing contact is at rest.
PTL 1 is intended to efficiently move the driven-side arcing contact with the minimum driving force in a time domain necessary to break an electric current.
PTL 2 proposes a double motion system using a grooved cam. This is a system in which a pin moves inside the grooved cam in association with the motion of driving-side components, this motion rotates the grooved cam, and consequently, a driven-side arcing contact in connection to the grooved cam is driven in the direction opposite to a driving-side arcing contact. The grooved cam can have any shapes, which can achieve desired velocity ratios of the driven-side arcing contact to the driving-side arcing contact.